skratchdot/color-blind

/*
 * color-blind
 * https://github.com/skratchdot/color-blind
 *
 * see blind.js for more information about the original source.
 *
 * Copyright (c) 2014 skratchdot
 * Licensed under the MIT license.
 */
'use strict';

var onecolor = require('onecolor');
var Blind = require('./blind.js').Blind;
var colorVisionData = {
    protanomaly: {type: "protan", anomalize: true},
    protanopia: {type: "protan"},
    deuteranomaly: {type: "deutan", anomalize: true},
    deuteranopia: {type: "deutan"},
    tritanomaly: {type: "tritan", anomalize: true},
    tritanopia: {type: "tritan"},
    achromatomaly: {type: "achroma", anomalize: true},
    achromatopsia: {type: "achroma"}
};
var denorm = function (ratio) {
    return Math.round(ratio * 255);
};
var createBlinder = function (key) {
    return function (colorString, returnRgb) {
        var color = onecolor(colorString);
        if (!color) {
            return returnRgb ? {R:0,G:0,B:0} : '#000000';
        }
        var rgb = new Blind({
            R: denorm(color.red() || 0),
            G: denorm(color.green() || 0),
            B: denorm(color.blue() || 0)
        }, colorVisionData[key].type, colorVisionData[key].anomalize);
        // blinder.tritanomaly('#000000') causes NaN / null
        rgb.R = rgb.R || 0;
        rgb.G = rgb.G || 0;
        rgb.B = rgb.B || 0;
        if (returnRgb) {
            delete rgb.X;
            delete rgb.Y;
            delete rgb.Z;
            return rgb;
        }
        return new onecolor.RGB(
            (rgb.R % 256) / 255,
            (rgb.G % 256) / 255,
            (rgb.B % 256) / 255,
            1
        ).hex();
    };
};

// add our exported functions
for (var key in colorVisionData) {
    exports[key] = createBlinder(key);
}